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As written on the post topic, you can expect to find on this upcoming list, services that don't require registration, nor download from any kind in order to use them. Tools that are really easy-to-use (most of them are single-page sites), and basically web-applications that can help on your daily internet visit/work. To be honest, it is not so hard to create lists of web 2.0 services, especially if you own a blog or a directory that contains relevant content. BUT it is definitely not easy to isolate the most useful ones from hundreds of sites.

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